Alkyl acrylate polymer having less odor

Abstract

Compositions containing copolymers of ethylene, alkyl acrylate and monoalkyl esters of 1,4-butenedioic acid and compounds having the formula ##STR1## formed by reacting the minor amount of alkyl acrylate monomer entrained in the copolymer with a secondary amine of the formula ##STR2## are less odorous than are compositions containing the unreacted alkyl acrylate monomer.

I claim: 
     
       1. A composition comprising (a) a copolymer containing polymerized ethylene units, polymerized alkyl acrylate units and polymerized units of a monoalkyl ester of 1,4-butenedioic acid, said alkyl acrylate units being selected from the class consisting of methyl acrylate and ethyl acrylate, the alkyl group of the monoalkyl ester having 1 to 6 carbon atoms, said alkyl acrylate units being present in the amount of 40 to 65% by weight of the polymer, said monoalkyl ester units being present in the amount of 1 to 10% by weight of the polymer, said ethylene units being present in a complemental amount, said polymer having a melt index of 0.3 to 100 grams/10 min. and (b) a compound having the formula ##STR9## where R' is an organic diradical containing at least 4 carbon atoms, and R" is an alkyl group of the same size as the alkyl group of the alkyl acrylate, said compound being present in the amount of between about 0.15 and 2% by weight of the composition said compound having been formed by the reaction of monomeric alkyl acrylate entrained in the copolymer and a secondary amine having the formula ##STR10## 
     
     
       2. The composition of claim 1 in which the polymerized units are randomly distributed in the polymeric molecules. 
     
     
       3. The composition of claim 2 which also contains 0.3 to 5 parts per 100 parts by weight of copolymer of a polybutadiene resin having a molecular weight of about 1000 to 3000 and above about 85% by weight pendant vinyl groups. 
     
     
       4. The composition of claim 3 also containing fillers. 
     
     
       5. The composition of claim 1 in which the polymerized alkyl acrylate units are methyl acrylate, in which the monoalkyl ester of 1,4-butenedioic acid is ethyl hydrogen maleate, in which R' has the formula --(CH 2 ) 2  --O--(CH 2 ) 2  -- and in which R" is methyl, and in which the concentration of the (b) component in the composition is 0.2 to 1% by weight of the composition. 
     
     
       6. The process for reducing the odor of a polymer of ethylene, alkyl acrylate and a monoalkyl ester of 1,4-butenedioic acid where the alkyl acrylate is selected from the class consisting of methyl acrylate and ethyl acrylate, and the alkyl groups of the ester contain 1 to 6 carbon atoms, containing minor amounts of the monomeric alkyl acrylate, which comprises combining with the polymer a secondary amine having the formula ##STR11## where R' is an organic diradical having at least 4 carbon atoms, under conditions such that at least a portion of the alkyl acrylate monomer reacts with the secondary amine to form a compound having the formula ##STR12## where R" is an alkyl group of the same size as the alkyl group of the alkyl acrylate. 
     
     
       7. The process of claim 6 in which the amount of secondary amine added to the polymer is at least equal on a mole basis to the amount of monomeric alkyl acrylate present in the copolymer. 
     
     
       8. The process of claim 7 in which the amount of secondary amine added to the polymer is on a mole basis from 1 to 3 times the amount of monomeric alkyl acrylate present. 
     
     
       9. The process of claim 8 in which the secondary amine is selected from the class consisting of morpholine, pyrrolidine, piperidine, homopiperidine, 1,2,3,4-tetrahydroisoquinoline, ethyl isonipecotate, α-pipecoline, 4-benzylpiperidine, 1-benzylpiperazine, and 1,2,3,6-tetrahydropyridine, the alkyl acrylate is methyl acrylate, and the addition to the polymer is carried out while the polymer is at a temperature between about 25° C. and 180° C. 
     
     
       10. The process of claim 9 in which the monomeric methyl acrylate content of the polymer is about 0.3 to 1% by weight of the polymer prior to the combining with the secondary amine.